The New Zealand rugby community is aware of safety issues at the junior level and has applied weight limits for each tackle grade to minimise injury risk. However, the current weighting system has created an unaccommodating situation for heavier participants as they do not play within their peer group. Using approximately 20,000 observations of junior rugby players across eight seasons (2009-2016), the study determines the likelihood of a junior New Zealand player returning the following season and isolating the drivers of this behaviour. Applying logistic regression and repeated measures analyses to determine whether participants who are above the specified weight limit for their age group are more likely to leave the game.

Investigating the impact of age in relation to the January 1st cut-off, this study found statistically significant churn rates at all age levels, except 10 years, for children who do not play with their peers. Children 11 years old who are playing up a grade by weight are 46% more likely to churn, compared to a player who is in the same team as their peers. Proportionally, these numbers are small, impacting approximately 3.5% of children in Auckland. However, a decline in playing numbers generally along with a clear and systematic trend for children to leave the game requires custodians of the junior game to take pragmatic action. Therefore, the present study recommends that peer relationships are considered alongside weight attributes.